• Journal of the Optical Society of Korea
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• 제11권2호
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• pp.76-81
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• 2007

The compound refractive X-ray lens (CRL) for focusing hard X-rays is investigated to determine the parameters such as the focal length, the focal spot size, and spatial distribution at the focal spot using a simple theoretical calculations and CRLs fabricated by the self-assembly method. The number of individual compound lenses are defined for the given focal length of 1 m. The X-ray energy of 1 to 40 keV is used in the calculations. The CRL for focusing hard X-rays which generated from the X-ray tube is fabricated by nanoparticle-polymer composite in the form of circular concaves. The self-assembly method is applied to form the nanoaluminum-poly (methly meth-acrylate) composite and carbon-polymer composite CRL lenses. Aluminum nanoparticles of 100 nm and carbon microparticles are diffused in the polymer solution then the high gravity up to 6000G is applied in it to form the concave lens shape. X-ray energy at 8 keV is used for characterization of the composite CRLs. The FWHM of intensity for the fabricated nanoaluminium composite CRL system, N=10 is measured as 1.8 mm, which would give about $70{\mu}m$ in FWHM at 1 m of the focal length.

• 대한수의학회지
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• 제54권1호
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• pp.59-62
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• 2014

A 12-year-old, castrated male Yorkshire terrier dog presented with frequent regurgitations that had begun 45 days earlier and become more progressive. Radiographs revealed an air-trap region behind the cranial esophageal sphincter muscle in the esophagus and esophagographies with barium contrast showed mild esophageal dilation with decreased motility. Esophageal motility increased within 5 min of neostigmine methylsulfate administration and acetylcholine receptor antibodies titer increased to beyond the normal range. Based on these findings, acquired myasthenia gravis with focal form was diagnosed, making this the first such case diagnosed by an acetylcholine receptor antibody test in Korea.

• 대한수학회보
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• 제38권2호
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• pp.285-292
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• 2001

The authors compute the Ricci curvature of the GRW space-time to obtain two conditions for the conjugate points which appear as the Timelike Convergence Condition(TCG) and the Jacobi inequality. Moreover, under such two conditions, we obtain a lower bound of the length of a unit timelike geodesic for focal points emanating form the immersed spacelike hypersurface, the graph over the fiber in the GRW space-time.

• 음성과학
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• 제8권2호
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• pp.165-180
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• 2001

In this paper prosodic characteristics of French language are analysed with a corpus of radio interview. Intonation patterns are interpreted in terms of raising pattern, focal raising pattern and falling pattern. Accentual prominence is classified in two types, rhythmic accent and focal accent. Focal accent permit to explain the cohesion in a utterance or between two utterances. As a prosodic variable of discourse pauses are described by their form of realization (filled pause, silent pause, hesitation etc), their distribution and their function in utterance.

• 치과방사선
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• 제21권1호
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• pp.119-125
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• 1991

In the study of magnification of image in the focal trough of panoramic radiography, (Yoshida company Panoura - Eight - s), a series of 63 x-ray films were taken with the 8-19 metal pins placed in the holes of the plastic plate, measured and evaluated by 4 observes. The author analyzed the vertical and horizontal magnification rate in the corrected focal trough. Results were as follows: 1. For vertial measurements, magnification rates were minimum 10% maximum 36% and the magnification for image of medial side was larger than that of image of lateral side from image layer. 2. For horizontal measurements, magnification rates were minimum-14% maximum 46% and images of medial side from focal trough were magnified and images of lateral side from focal trough were retrenched. 3. When moved 10㎜ downward occlusal layer, interspace was somewhat narrow between the pins and upper sides of pins were horizontally magnified but images of the end parts of pins showed tapered form. 4. When moved 10㎜ downward from the occlusal layer, opposite images showed overlapping.

• ETRI Journal
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• 제45권2호
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• pp.291-303
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• 2023

Selfies are a popular form of photography. However, due to physical constraints, the compositions of selfies are limited. We present algorithms for creating virtual portraits with interesting compositions from a set of selfies. The selfies are taken at the same location while the user spins around. The scene is analyzed using multiple selfies to determine the locations of the camera, subject, and background. Then, a view from a virtual camera is synthesized. We present two use cases. After rearranging the distances between the camera, subject, and background, we render a virtual view from a camera with a longer focal length. Following that, changes in perspective and lens characteristics caused by new compositions and focal lengths are simulated. Second, a virtual panoramic view with a larger field of view is rendered, with the user's image placed in a preferred location. In our experiments, virtual portraits with a wide range of focal lengths were obtained using a device equipped with a lens that has only one focal length. The rendered portraits included compositions that would be photographed with actual lenses. Our proposed algorithms can provide new use cases in which selfie compositions are not limited by a camera's focal length or distance from the camera.

• Annals of Clinical Neurophysiology
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• 제22권2호
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• pp.125-128
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• 2020

Focal eosinophilic myositis (FEM) is the most limited form of eosinophilic myositis that commonly affects the muscles of the lower leg without systemic manifestations. We report a patient with FEM who was studied by magnetic resonance imaging and muscle biopsy with a review of the literature.

• The Korean Journal of Pain
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• 제18권1호
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• pp.89-91
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• 2005

Essential hyperhidrosis is a socially disabling and emotionally embarrassing condition. Localized excessive sweating in the sacrococcygeal region is a rare form of focal hyperhidrosis. Although numerous treatment options exist, including botulinum toxin and sympathetic neurolysis, there has been no generally accepted form of treatment. The following cases describe the successful reduction of excessive sweating in the sacrococcygeal region, without side effects, after local applications of topical glycopyrrolate and the use of fast drying clothes.

• 제어로봇시스템학회논문지
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• 제6권5호
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• pp.396-403
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• 2000

A thermal imaging system is implemented for the measurement and the analysis of the thermal distribution of the target objects. The main part of the system is a thermal camera in which a focal plane array typed sensor is introduced. The sensor detects the mid-range infrared spectrum of target objects and then it outputs a generic video signal which should be processed to form a frame thermal image. Here, a digital signal processor(DSP) is applied for the high speed processing of the sensor signals. The DSP controls analog-to-digital converter, performs correction algorithms and outputs the frame thermal data to frame buffers. With the frame buffers can be generated a NTSC signal and transferred the frame data to personal computer(PC) for the analysis and a monitoring of the thermal scenes. By performing the signal processing functions in the DSP the overall system achieves a simple configuration. Several experimental results indicate the performance of the overall system.

• 한국광학회지
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• 제11권6호
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• pp.385-389
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• 2000

본 논문에서는 원형 대칭 광 시스템에 대한 초점 심도를 증가시키기 위해 Wigner 분포 함수(WDF)로 유도된 위상 지연 함수를 이용한다. 1차원 신호에 대한 WDF는 위상-공간($\chi,\zeta$)상의 2차원 함수로 표현되고 Strehl 비 (SR)를 이용해 정규화된 복사조도로 나타낸다. 초점 심도의 증가는 WDF 공간상에서 간단한 조작으로 자유공간 전파의 특성을 나타내는 전단 기울기 $\alpha$을 부여함으로서 달성된다. 또한 $\alpha$을 초점 심도의 항 $\delta_z$로 표현함으로서 위상 지연 함수를 통해 정량적으로 초점특성을 평가할 수 있는 방법을 제안한다. 제안된 방법으로 수치 해석한 결과를 다른 접근법으로 수행되었던 연구결과와 비교한다.